1. Field
The following description relates to a data recovery technique and, more particularly, to a data recovery technique using bit logging.
2. Description of the Related Art
One of the factors that may affect the performance of a database management system (DBMS) or a file system is recovery management of the DBMS or file system. A log for updated database or file may be recorded to recover from potential system failures.
The DBMS or file system recovery may be based on duplicate information. For example, information contained in a database or a file is stored in duplicate so that the information can be recovered if a system failure occurs. In such a duplicate method that uses a log, when a database or a file is updated, old and new values of the updated data item are separately recorded.
In DBMS or file system recovery, redo or undo operation is typically performed. A redo operation changes a value of an updated data item to a newly updated value. An undo operation changes a value of an updated data item to a value prior to the update.